Spencer Johnson, a onetime physician and children’s book author, whose best-selling books on business management, including “The One-Minute Manager” and “Who Moved My Cheese?,” sold millions of copies and inspired a cultlike following, died July 3 at a hospital in Encinitas, Calif. He was 78.

The cause was pancreatic cancer. His death was first reported by the San Diego Union-Tribune.

In the mid-1970s, Dr. Johnson gave up medicine to write inspirational books for children, all with the word “value” in the title, such as “The Value of Honesty: The Story of Confucius.”

By the early 1980s, he discovered a new formula, teaming with management consultant Kenneth Blanchard on “The One-Minute Manager,” which urged businesspeople to connect with their workers by spending a full minute giving sincere praise (or, if necessary, a reprimand).

Dr. Johnson and Blanchard sold thousands of self-published copies of “The One-Minute Manager,” incorporating changes suggested by business leaders.

“That’s what we call writing for the marketplace,” Dr. Johnson said.

When “The One-Minute Manager” was picked up in 1982 by a New York publisher, Morrow, it became an instant bestseller. It also represented a marketing triumph for the authors, who insisted that it carry the steep cover price of $15, despite having barely 100 pages of text. It came with a money-back guarantee.

Dr. Johnson then spun off a series of follow-ups, including “The One-Minute Father,” “The One-Minute Mother” and “One Minute for Myself.”

“It’s the one minute you stop during the day and look at what you’re thinking and what you’re doing,” he said in 1986. “The real key is that quiet time you listen for your own wisdom.”

Listening to his inner wisdom or perhaps the voice of opportunity, Dr. Johnson later embarked on his signature literary effort, “Who Moved My Cheese?”

Subtitled “An A-Mazing Way to Deal With Change in Your Work and in Your Life,” the 94-page book, published in 1998, became a No. 1 bestseller, largely through word of mouth and the testimonials of chief executives from such companies as Procter & Gamble and Hewlett-Packard.

The book is a parable built around four characters: two mice, named Sniff and Scurry, and two people, Hem and Haw. All four live in a maze and survive happily on cheese until one day their cheese disappears.

The mice immediately scamper away to find a new source of cheese, while Hem and Haw grouse about their fate and their growing hunger. Eventually, in this tale of mice and men, Haw decides the mice are right, and he goes off to discover what may be in store around the next corner.

He scrawls helpful tips on the walls of the maze, such as “The Quicker You Let Go of Old Cheese, the Sooner You Find New Cheese.”

The lesson, as old as commerce itself, is that it pays to adapt to changing circumstances.

People ate it up, so to speak. Although the book never reveals who actually moved the cheese, “Who Moved My Cheese?” was studied in business schools, was distributed by the thousands to employees and was applied to endeavors of every kind.

Preachers hailed it from the pulpit, and it was featured at conventions of dentists and hotel managers. Washington Redskins running back Brian Mitchell said the message of turning “the negative into positive” gave him an edge on the gridiron.

“My cheese is to get to the playoffs,” he said.

Even though the Financial Times described “Who Moved My Cheese?” as “a 94-page work of stupefying banality,” that didn’t stop it from being translated into 44 languages and selling more than 28 million copies. Dr. Johnson reportedly kept 50 percent of the original cover price of $19.95.

“Everywhere I went, people were asking me to write this book,” he told The Washington Post in 2000. “It’s so simple and unthreatening. As you watch the characters, you can discover yourself in the story.”

For some people, Dr. Johnson’s cheese metaphor had an almost magical quality. Others scoffed that an idea that could mean anything really had no meaning at all.

“Smell the Cheese Often,” notes one of the book’s pungent pieces of advice, “So You Know When It Is Getting Old.”

Dr. Johnson went on to market a line of coffee mugs, pens, videos and conferences, known as the “Cheese Experience,” and published versions of his book for children.

Others, however, found “Cheese” ripe for mockery, and one parody was published with the inevitable title of “Who Cut the Cheese?”

Patrick Spencer Johnson was born Nov. 24, 1938, in Watertown, S.D., and grew up in Los Angeles. His father was a builder and investor.

Dr. Johnson graduated from the University of Southern California in 1963 and from the Royal College of Surgeons in Dublin in 1968.

He abandoned medicine, he said, after concluding that the underlying causes of illness were largely rooted in the mind rather than the body. He published more than a dozen children’s books before embarking on his “One-Minute” series in the 1980s.

Dr. Johnson lived, at various times, in Hawaii, New Hampshire and California. He gave frequent interviews but refused to have his photograph printed with his books.

His first marriage, to Ann Donegan, ended in divorce. His second wife, Lesley Bostridge, died in 2009. Survivors include three sons, a brother and a sister.

Dr. Johnson said it took him years to write his books, which were typically composed in the simple, folksy style of the parable.

“I chose it because it’s a most enjoyable format to read,” he said in 1986. “People don’t like to work very hard at anything.”